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Lose Weight: How Bariatric Surgery Works

Obesity is a rising medical problem in the United States. According to the CDC, more than one-third of adults have obesity. Obesity-related conditions include heart disease, stroke, type 2 diabetes and certain types of cancer, some of the leading causes of preventable death.


When our weight is in a healthy range, our body more efficiently circulates blood, our fluid levels are more easily managed, and we are less likely to develop such diseases and cancers. Several factors can contribute to obesity, but many steps can be taken to lose weight and live a healthy lifestyle.


There is no one operation, diet or medication that can by itself offer a permanent cure. Weight loss surgery is one of the many ways to help treat obesity. Surgery with good aftercare, healthy eating habits and moderate lifestyle changes is one way give positive long-term results for health and weight.


The process of determining if a person is a good candidate for bariatric surgery takes time. There are other ways to lose weight that do not include surgery. Health care professionals will typically recommend non-surgical weight-loss options before bariatric surgery, such as a medical weight loss program. However, if a patient is still considering a surgical approach, they’ll be referred to a specialist in bariatric surgery.


Patients undergo a series of tests to establish their physical and mental preparedness for this life-changing procedure. They can expect to go through a four to eight month evaluation period before the surgery. Some required tests our patients need are a complete blood count (CBC), urinalysis, chemistry panel, chest X-ray and electrocardiogram. They also may also need a glucose tolerance test to find out whether or not they have diabetes.


These tests are important and necessary to preparing for surgery. These assessments are the best way to avoid complications because they help us to understand our patient. During surgery, our patients are high risk because of the health problems they typically have. 


What is bariatric surgery?

There are different types of bariatric surgery.

  • Adjustable banding — You may have heard of the LAP-Band®. This is a system that can be implanted during adjustable banding surgery.

    The banding is used to reduce your stomach’s capacity. After the surgery, you won’t be able to eat as much food in one sitting because you’ll feel full faster and with less food. Some people are able to lose 50 to 60 percent of their extra weight after this surgery.

    During this surgery a few small incisions are made and the band is surgically wrapped around your stomach. The band, sometimes called a belt, is connected via a tube to a port under your skin. The doctor can inject sterile salt water into the band to inflate it and create a small pouch in the upper part of your stomach.

    Food you eat goes into the pouch were the nutrients are absorbed. Since what you eat fills up the pouch rather quickly, you feel full with less food. The reduced food absorption results in weight loss.
  • Gastric sleeve — Unlike adjustable banding, the gastric sleeve permanently reduces the size of your stomach. During the procedure, using a few small incisions, a part of your stomach is removed. The stomach then resembles a sleeve.

    As with banding, your appetite is less and you’ll feel full more quickly and for a longer time. After this surgery, typical patients lose 55 to 65 percent of their extra weight.
  • Roux-en-Y gastric bypass — Pronounced “ROO-on-why,” this procedure is the most common weight-loss surgery. You may also hear it called gastric bypass or stomach stapling. This procedure uses small incisions to surgically reduce the size of the stomach by using staples to separate a part of the stomach, creating a small pouch.

    As with other procedures, this pouch is where nutrients from food are absorbed into your body. You’ll feel fuller fast and eat less food. This surgery typically results in patients losing 60 to 70 percent of extra body weight.


If you’re a good candidate for bariatric surgery, your surgeon will discuss your options and help you make an informed decision.


Healthy lifestyle choices give the best results for health and quality of life after surgery. After the procedure, our surgical team wants to ensure successful long-term weight loss for our patients. This is achieved by following the diet and exercise recommendations our surgeons give.Any surgery involves risks. These surgeries can result in infections, hernias and blood clots. Those who have had one of these surgeries can expect to require medical follow up for the rest of their lives, and we strive to be there each step of the way to help our patients continue to live well.


Who is a good candidate for bariatric surgery?

A way to measure how much body fat a person has is to determine their body mass index (BMI) using a BMI calculator.

Candidates for bariatric surgery usually have:

  • A BMI of 40 or more.


  • A BMI of 35 or more with a serious obesity-related health problem such as type 2 diabetes, heart disease or sleep apnea.
  • (For the gastric band only) A BMI of 30 or more with a serious obesity-related health problem.


If you’re considering bariatric surgery, a number of online resources are available, and of course you’ll want to seek the guidance of your health care professional.

Losing weight isn’t just about the food that’s consumed. It’s all about the lifestyle. Healthy amounts of sleep, stress management and being active also are very important. Living life with a healthy weight is one of the ways you can help ensure you live well throughout your life!

Meet the Author

John B. Newman, MD, specializes in general surgery and is the hospital president of Aurora Medical Center in Oshkosh.

Read more posts from this author

The information presented in this site is intended for general information and educational purposes. It is not intended to replace the advice of your own physician. Contact your physician if you believe you have a health problem.

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